Powder case lock for breech mechanism



Oct. 15, 1957 J U D 2,809,561

POWDER CASE LOCK FOR BREECH MECHANISM Filed Oct. 29, 1954 2 Sheets-Sheet 1 FIG. I

INVENTOR JAMES M. EDMUND BY 11mm ATTORNEYS Oct. 15, 1957 EDMUND 2,809,561

POWDER CASE LOCK FOR BREECH MECHANISM Filed 001;. 29, 1954 2 Sheets-Sheet 2 IN VENTOR JAMES M. EDMUND BY QB W ATTORNEYS V 2,809,561: POWDER cAtsE ock Fort" BREECH MECHANISM James Mr Edmund, Montgomery? County, Mdi," assignor to the United States of America as represented" by the Secretary of the Navy Application October at, 1 9521 SerialNo. 465,762

2 Claims; case-24 (Grantedunde'i-Title 35-, us; Code 1952 sec; 266) catapult breech mechanisms inthe most accessible place.

Hence", the breech mechanisms are not conveniently available to loadersand, in addition, at the time loading and reloading operations take place, there is frequently confusion on board, perhaps blackout or dimout precautions are in progress and ifthe ship is at sea it is subject to violent motion from wind and waves. Under such circumstances it is of course desirable that automatic interlock mechanisms be provided to prevent jams or accidents such as might occur if a powder case containing the catapult charge were to slip'back out of the breech during thcflloadiug processta Accordingly, thepresent invention has for an. object the provision of simple,..automatic= means for'retaining a powder case in the breech of a catapult mechanism at sea whereby a case when once inserted in the breech cannot accidently become displaced and dropped from the breech even though the breechblock has not gone into place behind the case.

It is another object of the present inventon to provide an automatic powder case lock for the breech mechanism of abreech loaded powder case firing mechanism.

Another object is to provide a simple elfective latch means to retain a powder case in place when the breech has been opened, the mechanism of which will not interfere with normal operation of the breechblock.

Another object is to provide a powder case latch mechanism which is automatically rendered inoperative upon actuation of thepowder case extractor mechanism.

A further object is to provide a simple, safe, reliable and foolproof means for preventing accidental displacement of a powder case from a breech.

Other objects and many of the attendant advantages of this invention will be readily appreciated as the same becomes better understood by reference to the following detailed description when considered in connection with the accompanying drawings wherein:

Fig. 1 is a vertical sectional view partly in elevation of a breech mechanism embodying the present invention Fig. 2 is a change position view of the upper portion of the embodiment of Fig. 1 showing the positions of the parts just after initiation of case extraction; I

Fig. 3 is a view similar to Fig. 2 showing the positions of the parts at the completion of extraction movement; and

Fig. 4 is a perspective view of the integral extractor arms, shaft and operating lever.

In the embodiment illustrated in the drawings there is shown the breech end of a barrel which receives a 28. Lever 28 is connected at its uppermost tip 29 by powder ca'se having a flange 12 at one end. The; periphery of this' b'a'r rel isthreaded to receive a housing- 13 whlch h'as'-a=vertical1-well 14 to receive a vertically reciprocable breechblock 15.; The breechblock 15 is centrallyarelieved along its upper surface to provide a saddle the bottom of which aligns with the lower edge of the opening in barrel 10 when the breechblock is in:

its lowered position as illustrated in Fig. 1

The breechblock 1 5'ismounted for up and downmovement in the usual way by suitable breechblock operating means, not forming a part of this invention, and may employ vertical ribs on the side of the block to engage with inclined'gro'oves in the vertical Well so that as the breechblock 15 is raised it. is also wedged toward the base of the barrel to hold a powder case in place during firing. Thebreechblock thus forms a vertical sliding- Wedge movable in the vertical well of the housing The after portion of the housing is also provided with a circularopening I9 which registers with the barrel 1 1', and' it will be apparent that when the breechblock is re tracted to its position shown in Fig. l a powder case inthe breech could accidently be displaced and fall out of the barrel with possibly serious results to equipmentand personnel inthe vicinity. Also, if the breechblock were to be raised while the powder case was partially outof the barrel, a jam would be sure to occur.

Toprevent unintentional rearward movement of the powder case the present invention employs a powder case latch located in the upper part of the vertical well' 1'4. and including a shoe 20 pivoted to an inside wall of the well at 21 and cooperating with a spring 22 which urges the toe 23 of the shoe downwardly into position immediately behind the base of the powder case 11. It. will be noted that the lower surface of the shoe is formed toprovide a cam surface against which the leading edge of a case being loaded may bear to cause the shoe to rise and permit the case to pass into the barrel. Whenthe case flange 12 is snugly seated against the rear face of the barrel, the shoe will be forced downwardly by spring 22 to bring the tip 23 behind the flange and posi-' tively lock the powder case in place.

Intermediate the ends of the latch 20 there is provided a lift pin 24 which fits in the elongated slot 25 of a latch lifting link 26. The upper end of this link is connected by a pin 27 with the heel of an extractor operating lever link 30 with a piston and rod 31 which is reciprccable by fluid entering an ejector cylinder 32 through port 33 or 34. As shown in Fig. l the ejector cylinder 32 is secured to the housing 13 by a band 35 which encompasses the housing and also supports a guide bracket 36 having a pivot slot 37 to receive slidable pivot pin 38 on the extractor operating lever 28.

As best shown in Fig. 4 the extractor operating lever 28 is Welded or otherwise integrally secured to a transversely extending extractor arm connecting shaft 39 to the ends of which are welded or otherwise integrally secured depending extractor arms 46 having inturned case flange engaging tips 41 which are received in suitable recesses 42 on opposite sides of the barrel 10.

The shoe is normally urged downwardly by spring 22 into the position illustrated in Fig. l to block rearward movement of the powder case, but during case loading operation the shoe 20 is cammed upwardly by the case as Also the shoe raises into place behind a powder case. In addition the shoe is raised automatically by the linkage shown when a case is forcefully extracted in which event hydraulic fluid is ported into extractor cylinder 32 by way of port Patented Oct. 15, 1957 34 and moves the piston rod 31 to the left. Initial movement pivots the extractor lever 28 and integral extractor connecting shaft 39 together with the integral extractor arms 40 to the left, the parts pivoting about the rounded inturned tips 41 at the lower ends of the extractor arms so as to shift cam pin 38 part way along the arcuate cam slot 37 as shown in Fig. 2. This initial movement lifts the heel of the operating lever 23 and, through link 26 having slot 25 acting upon pin 24, lifts the toe 23 of the powder case shoe 20 out of the path of the flange 12 of the powder case.

Continued movement of the piston and rod 31 to the left brings the parts into the position illustrated in Fig. 3 where pin 3'8 is bottomed against the left end of slot 37 and, with this point as a pivot, the rounded lower ends 41 are kicked to the rear, rapidly propelling the powder case through opening 19 in the housing 13.

It will be apparent that the slot 25 in the lower end of the latch lifting link 26 permits upward movement of the shoe 20 without affecting the operation of the extractor arms; likewise, it will be apparent that upon the admission of hydraulic fluid into extractor cylinder 32 through port 33, the reverse operation will take place and the movable pivot pin 38 will cam to the lowermost right-hand position in slot 37 before the lower ends 41 of the extractor arms 40 will be moved back into slots 42 in the barrel.

Obviously many modifications and variations of the present invention are possible in the light of the above teachings. It is therefore to be understood that Within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

1. A powder case lock for a breech mechanism comprising; pivotally mounted spring biased latch means normally extending into the path of the powder case and being displaceable by case engagement therewith during breech loading so as to engage behind the case and retain the case in the breech, extractor arms having arcuately shaped tip portions engaging the case flange for extraction thereof, said extractor arms being connected to said latch means for moving the latch means to a position disengaged from the case, an operating lever rigidly secured to said extractor arms for movement therewith, pivot means mounted on the operating lever, and means for moving said extractor arms about the arcuately shaped portions of their lower tips during the initial extractor movement so as to move the powder case latch out of case latching position and for subsequently moving the extractor arms about the pivot means on the operating lever to thereby cause extraction of the powder case.

2. A powder case latch mechanism for a breech comprising; a shoe pivotally connected to the upper wall portion of the breech, said shoe having a one-way cam surface for engaging a powder case as the latter is loaded into the breech, said shoe being of a length sufficient to snugly engage the base end of the powder case and latch the powder case in a loaded position to prevent longitudinal movement of the case, means for biasing said shoe into a latching position, an extractor arm connecting shaft rotatably disposed adjacent the breech, an extractor arm rigidly secured at each end portion of said connecting shaft, a bell crank operating lever rigidly connected at one end thereof to said connecting shaft and having a linearly displaceable pivotal mounting on said breech, a pivotally mounted link operatively connected between intermediate portions respectively of said lever and said shoe, means connected to the remote crank end of said operating lever for moving the latter and to swing said shoe against the action of said biasing means to an unlatched position and thereafter elTect movement of the extractor arms to extract the powder case from the breech.

References Cited in the file of this patent UNITED STATES PATENTS 879,225 Wheeler Feb. 18, 1908 2,402,581 Ruau June 25, 1946 2,415,953 Lowe et al. Feb. 18, 1947 2,741,160 Musser Apr. 10, 1956 

